JPS6049176B2 - Method for producing fluorinated α-carboxyl-ω-carbonyl fluoride - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorinated α-carboxy-ω-carbonyl fluoride and a method for producing the same.

As described in US Pat. No. 3,546,186, issued Dec. 8, 1972, fluoromonomers containing carboxyl or carboxylic ester groups have been difficult to prepare.

Such monomers are useful in making fluoro homopolymers or copolymers with tetrafluoroethylene. Therefore, it would be advantageous to be able to easily produce fluoromonomers.
CF2Q when Q is COOH)COOalkyl or COF.

The symmetrical difluoromalonic acid compounds of [E, J
, P. Fear et al., J. ApplChem.
, 5, 589-594 (1955); and J. Heicklen, J. Phys. Chem.
70, 618-627 (1966)]. Liazanova (
Rya2anova) et al., Zh. Vses, Khlm,
Ohchest917, 347-8 (1972)
The formula ROOC(CF.

) nCOF compounds are described. According to the method of the invention, 503 can be converted to the formula ROOC-CF2-CF2-O
A method for producing ROOC-CF2-COF is provided, which comprises contacting the compound with a compound of R' (wherein R and R' may be the same or different and are alkyl having 1 to 6 carbon atoms).

Compounds of the invention have the formula COORCF3 )・l C.F.

-TaF. -O-CF4C0FI'n [In the formula, R is alkyl having 1 to 6 carbon atoms, particularly mephthyl or ethyl, and n is 0 to 6] Among the fluorine-containing compounds where n is 0 α-carboxy-ω-carbonyl fluoride.

The compound H3COOC-CF2-COF is most preferred. Compounds of the invention can be prepared using lower alkyl β-alkoxytetrafluoropropionates [Wlle
y) of US Pat. No. 2,988,537] with sulfur trioxide.

Compounds of formula (1), on reaction with hexafluoropropylene oxide, give α-carboxy-ω-carbonyl fluorides of formula V with m=1 to 6, according to the equation.

The reaction between the compound of formula ■ and sulfur trioxide is an exothermic reaction,
Measures should be taken to dissipate the heat of reaction.

One method is to add a small portion of the alkoxy ester compound of formula (1) to SO while cooling with a reflux condenser or external cooling means.
This is the method of adding it to 3.

Alternatively, SO2 can be added in small portions to the alkoxy ester, but the former method is preferred. The reaction can also be carried out in a continuous manner by slowly feeding the reactants separately into a cooled reaction zone and then removing the product continuously. Sulfur trioxide can be used in either monomeric or polymeric form. The reaction is preferably carried out without solvent. However, the reaction may also be carried out in the presence of diluents that are relatively inert towards or bond to SO3, such as dioxane, chloroform, carbon tetrachloride, fluorocarbon liquids, and the like. The temperature at which the reaction is carried out is from about -30°C to about 250°C, preferably from about 0°C to 100°C. Pressure is not a critical variable, but subatmospheric and superatmospheric pressures can be used. S that can be introduced to carry out this reaction
The molar ratio of O3 and the compound of formula (1) can vary widely, for example from about 1:20 to 20:1, preferably about 2:1.
It is. The reaction of the compound of formula (1) with hexafluoropropylene oxide is preferably carried out in the presence of fluoride ions as a catalyst.

This can be done using suitable fluorides such as alkali metal fluorides such as cesium fluoride, potassium fluoride; silver fluoride;
Ammonium fluoride; tetraalkylammonium fluoride (alkyl; carbon number 1 to 4), such as tetramethylammonium fluoride, tetraethylammonium fluoride, and tetrabutylammonium fluoride, and sulfonium fluoride, such as benzenesulfonium fluoride. Therefore, it is easily achieved. The fluoride catalyst is commonly used in conjunction with an inert liquid diluent (preferably an organic liquid) in which the selected fluoride is dissolved at least 0.001%. The fluoride catalyst is about 0.01 to about 1 per mole of compound of formula
．． It can be used in amounts of 0 molar equivalents. Suitable diluents include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether and neutral solvents such as acetonitrile.
The reaction is somewhat exothermic and measures should be taken to dissipate the heat of reaction. The temperature used is about -50 to about 200℃
, suitably from about -10 to about 200<0>C. Pressure is not a critical variable and can operate above and below atmospheric pressure.
Hexafluoropropylene oxide is a gas over most of its operational temperature range, with pressures near atmospheric being preferred. The applicable molar ratio of hexafluoropropylene oxide to the compound of formula (1) is from about 1:20 to about 20:
1, preferably 1:1. As shown in Reference Examples, more than 1 mole of hexafluoropropylene oxide can be reacted with a compound of formula (1) to produce a compound of formula (2) where m is greater than 1.

In order to obtain products with high m values, high molecular weight proportions of hexafluoropropylene oxide are used and high pressures and low temperatures are selected. In order to obtain products with low m values (for example 1 or 2), compounds of the formula (1) are used in high molecular proportions and low pressures and high temperatures are selected. Each of the compounds of Formula 1 is a reactive organic compound that is a carboxylic acid ester and an acid fluoride.

Such fluorinated compounds are rare and are understood as such. The reason is that known methods for synthesizing difunctional carboxylic acid compounds! gives dicarboxylic esters and diacid fluorides, but teaches almost nothing about how to produce compounds having both a carboxylic ester group and a carbonyl fluoride group in the same molecule. When carrying out a reaction with compounds of formula 1, care must be taken to prevent their easy conversion to the more common corresponding dicarboxylic esters or dicarbonyl fluorides. Compounds of formula 1 are useful as intermediates in the preparation of new fluorine-substituted polymerizable olefinic compounds containing and having carboxylic acid or ester groups.

As shown in the reference example, a compound of formula 1 with n=0 is reacted with hexafluoropropylene oxide in the presence of a fluoride catalyst to produce a compound of formula 1 with n=1 to 6, such as a compound of formula V. . The compounds of formula V can be sequentially polymerized according to the equation, and a solid base can be polymerized over a salt, such as sodium phosphate, sodium carbonate or potassium carbonate, at a suitable temperature.

As shown in the reference examples, the monomer of formula (1) can be homopolymerized into heavy oils suitable as lubricants, and can be copolymerized with, for example, tetrafluoroethylene or chlorotrifluoroethylene to make it thermoplastic and It provides a tough solid polymer that can be hot-rolled or hot-rolled into sheets and packaging films as protective layers and as ion exchange membranes in electrolytic cells where extraordinary chemical stability is required.

These polymers are composed of repeating units [wherein p is O~5, q is O~20, X is all fluorine or 3 fluorine and 1 chlorine, and R'' is H or lower alkyl].

Suitable copolymers exhibit an average composition corresponding to p=1 or 2 and q=1 to 9. In each of the following examples, parts are by weight unless otherwise specified.

The sulfur trioxide was added to a three-tube flask connected to a distillation apparatus and equipped with a dropper and a thermometer.

Crude CH3OCF2CF2CO is added to the magnetically stirred sulfur trioxide at such a rate that it gently refluxes for an exothermic reaction.
OCH3 (100y) was added dropwise from the funnel.

When the addition was complete, the mixture was distilled at atmospheric pressure. 82～
According to gas chromatography analysis, the product distilled at 86°C is approximately 69.5y of H3COOC-CF2-COF.
(85%), and the remainder was mostly CH3OSO2F.

Pour this mixture onto sodium fluoride pellets at approx. C
/4 order, CH3OSO2F is CH3F and N
It was converted to aOSO2F. , then pure H3COOC
-CF2-COF was separated by distillation. Equipped with a dry ice condenser and gas, liquid and solid addition ports.
Tetraglyme (tetraethylene glycol dimethyl ether) 20yC3F in a 0TrLt glass flask
6.0y and crude H3COOCCF2COF (3% CH3
26.3y of OSO2F (containing OSO2F) was charged.

29.2y of hexafluoropropylene oxide (1+'PO) was slowly added while keeping the mixture below 15°C. Upon completion of the reaction, excess H3COOCCF
2COF and HF'PO were removed under vacuum at 40°C.
Distill the residue to obtain crude H3COOC-CF2-CF2-0-
CF(CF3)-COF was distilled at 75-95°C/400 rounds. Its structure was confirmed by the following means: IR
(Liquid): 190011820, 1330, 1250,
1140, 1035c7n-1PMR (CCl4
): 4.04ppm (singlet line) FMR (CCl4): +
21.6 (multiplet, IF), -82.4 (prode, multiplet, 4F'), -86.3 (multiplet, 1F), -11
9.8 (multiplet, 'f), -130 ppm (multiplet, 1F) Reference example 2150 m1 Carius tube (Car
iustube), 0.5y1 tetraglyme 3ml each of CsF and KF (vacuum dried at 400C), H3
COOC-CF2-CF2-COF34.5y and I (
I prepared FPO6Oy.

The tube was sealed and rotated overnight at room temperature. Distillation of the reaction mixture yields H3COOC-CF2-CF2-0-CF
(CF3)-COFl5q was obtained. boiling point, 65-C/1
007r$TO analysis: C7H3F9O4 calculated value: Cl2
6. lO; HlO. 94; Fl53. O9,. Experimental value:
Cl25.87; HIO. 89; Fl53.34 reference example 4H3C00CCF2C0F182f (1.17 mono(c)), powdered cesium fluoride (15g) was
1 of 4) into a lask and then stoppered except for the connections to the vacuum pump and manifold connected to the open-end manometer.

The flask was subjected to vacuum while Meeker
The cesium fluoride was completely dried by heating with a burner. After the flask was cooled, it was filled with dry nitrogen and then a large magnetic stir bar. Place a thermometer in the flask, vacuum again, and fill with nitrogen 20ml of tetraglyme and H3
COOCCF2COF63V (0.4 mol) was added.

The flask was then cooled to -10°C, degassed, and filled three times with hexafluoropropene oxide (1IF'PO) to a pressure of 600°C. Stirring was started and automatically maintained at 600 wft with a vacuum evaporator at a pressure of HFPO. 8P
Since 0 is constantly absorbed in the steam reaction, the temperature can be changed from O to -
Cooling was necessary to maintain the temperature at 10°C.

8P0140q(a). The reaction was stopped after 84 mol) had been absorbed.

The lower layer (190y) was distilled.

The resulting products are shown in the table below. The ratio of products formed could be varied depending on the reaction temperature and mainly on the amount of 6HFP0 used: without cooling (reacted at 55 °C) and HF
The method of Reference Example 3 was repeated except that the addition of PO was stopped after 190q was absorbed.

Distillation resulted in recovery of H3COOCCF2COFlOO9 and n:1 product 87.5f (0.27 mol, 2
3%), n = 2 organisms 40y (0.08 mol, 7,ゞ%
) and n=3 product 10y (0.015 mol, 1.3
%) was obtained. Reference Example 5 C3Fl5y except for using the apparatus and general method of Reference Example 3
Tetraglyme 20TrLtH3C00CF2CF20
The reaction of CF, (CF3)COF234f and IfPO63f was carried out at 68°C.

The distillation results in the abovementioned product 38y with n=2 (0.08 mol, 11%) and the product 6da with n=3 (0.01 mol,
1%). Application example A: 90 cc of fine-particle sodium phosphate (pre-dried at 400°C) having a diameter of 1 inch and a length of 12 inches and being stirred at the center by a motor-driven stainless steel screw.
While heating the particles to 235-240°C in an external separate furnace, H,C
OOCCF, CF2OCF (CF3) CF2OCF (C
F3) A COF of 6.4 da was passed for 9 minutes with a slow nitrogen flow.

Vapors exiting the bottom of the tube were condensed and collected in a trap cooled with dry ice-acetone. The liquid composition was distilled to yield 3.7 g (67%) of methyl 3-[2-trifluoroethenoxy)-1-(trifluoromethyl)-trifluoroethoxy]-tetrafluoropropionate.
Boiling point 98oC/110T0t. Analysis: C9l43F,3
O4 Calculated value: C, 25.6l; H, O. 72;F. ．． 58.
5l experimental value: C, 25.47; H, O. 8l; F, 59
．． 87(2)3-[2-(trifluoroethenoxy)-
Methyl 1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionate 2da and 1,1,2-
A glass tube containing 0.01 mL of a 6% solution of perfluoropropionyl peroxide in trichlorotrifluoroethane was sealed under vacuum and rotated overnight at room temperature.

After removing unreacted monomers under vacuum, 0.5 da of an oily homocopolymer having repeating units of the above formula was obtained. (3) Methyl 3-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionate 69, tetrafluoroethylene 1da and 1,1,2-trichlorotrifluoro 6% solution of perfluoropropionyl peroxide in ethane 0.0
A glass tube containing 1 ml was sealed under vacuum at liquid nitrogen temperature and then rotated overnight at room temperature.

The mixture became very viscous. The remaining tetrafluoroethylene is drained off and then further tetrafluoroethylene 5y and perfluoropropionyl peroxide 0
．． 01TfLL was sealed inside the tube. The tube was rotated for 5 hours at room temperature and then opened. After removing the volatiles under vacuum at 100'C, 0.6q of an elastomeric copolymer of the above repeating unit with q greater than 1 was obtained. Methyl 3-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionate 6.8y(
0.016 mol), tetrafluoroethylene 1.7y (
0.017 mol), 2 ml of 1,1,2-trichlorotrifluoroethane and 0.01 ml of a 6% solution of perfluoropropionyl peroxide in 1,1,2-trichlorotrifluoroethane. It was sealed at liquid nitrogen temperature, rotated at room temperature overnight, and then opened.

By separating the solid product and washing with ether,
Elastic copolymer 1.7f was obtained. Copolymer at 250 pS
The film was compressed at 250° C. to obtain a 3 mil film exhibiting strong infrared absorption of the ester carbonyl at 5.5 μm.
This film was mixed with water 35y and dimethyl sulfoxide (D
The mixture was heated to 100° C. for 3 hours in a solution of KOHl5y in 35 g of MSO). When the obtained film was examined by infrared light, absorption of carboxylic acid (-QH at 2.8μ and 5.95p
(C=0 broad absorption) replaced the ester carbonyl absorption. This indicates that a copolymer of the above repeating units with q greater than 1 was obtained. Using the apparatus and general method of use example A (1) above, H3COOCC
F2-[CF2OCF(CF3)]3C0F2.2y was passed over Na3pO4 at 235-240°C with a gentle nitrogen blanket. Distillation of the collected product yields 3-[2-(
2-[Trifluoroethenoxy]-1-[trifluoromethyl]trifluoroethoxy)-1-(trifluoromethyl)-trifluoroethoxy]methyl tetrafluoropropionate 12f (61%) was obtained; boiling point 7rc /
5.577!77! . Analysis: Cl2H3Fl9O5 Calculated value: Cl24.5O; H. ．． O. 5l: Fl6l. 38
Experimental value: Cl24.28:HlO. 68; Fl6l. 4
In a 4-part liquid Okito, crude H3COOCCF2CF2O
CF(CF3)CF2OCF=CF2 was shaken with 25 ml of 10% aqueous NaOH at room temperature.

The aqueous layer was separated and acidified with concentrated hydrochloric acid. The separated lower layer was distilled from a small amount of PO, yielding 10.7 V of 3-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionic acid: boiling point, 53 °C/0.25wrm. ．． n 5 = 1.
307 analysis: C8HF'1304 calculated value: Cl23.
54:H,. O. 25; Fl6O. 53: Neutral formula 408 Experimental value: Cl23.8O; HlO. 52; Fl6
l. 7l: Neutral formula 407.73-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionic acid 8.8
containing 2.2 da, tetrafluoroethylene, 13 ml of 1,1,1-trichlorotolyloethane and 0.01 ml of a 6% solution of perfluoropropionyl peroxide in 1,1,2-trichlorofluoroethane. The glass tube was sealed and rotated for 6 hours at room temperature.

Eject the gas and then add 0.01 of a 6% solution of perfluoropropionyl peroxide in tetrafluoroethylene 3 da and 1,1,2-trichlorotrifluoroethane.
mL was added. The tube was sealed, rotated overnight at room temperature, and then opened. After filtration and washing in ether, q is 1
2.3 g of a copolymer with the larger repeat unit described above was obtained. The compressed film obtained strong absorption of -COOH. Application Example A (Following the general method of 41, each of the 6 potassium tubes was charged with a
0.01 mL of % solution and methyl 3-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionate (vinyl ether), tetrafluoroethylene (TFE) shown in the table below.
) and 1,1,2-trichlorotrifluoroethane (solvent).

The tube was sealed at liquid nitrogen temperature, rotated overnight at room temperature, and opened. Each amount of copolymer was recovered by filtration, washed with ether, and dried. 6 copolymer products combined, 360
The film was compression molded at °C/20,000 PSI.

After hydrolysis in KOH-H2O-DMSO in Example A(4), the copolymer has a neutralization equivalent of 1500;
The copolymer was found to have an average composition represented by the above formula. (2) 8.8 g of 3-[2-(trifluoroethenoxy)-1-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionic acid, 2.2 g of tetrafluoroethylene
y11,1,2-trichlorotrifluoroethane 13m
13 ml of a 6% solution of perfluoropropionyl peroxide in t and 1,1,2-trichlorofluoroethane
and sealed for 6 hours at room temperature.

Emit gas, tetrafluoroethylene 3y and 1,
0.01 ml of a 6% solution of perfluoropropionyl peroxide in 1,2-trichlorofluoroethane was added. The tube was sealed and stirred overnight at room temperature, then opened. Filtration and washing in ether gave a copolymer 2.3V with the above-mentioned repeating units with q greater than 1. The compressed film showed strong absorption of -COOH. Usage example D (1) 3-[2-(trifluoroethenoxy)-1
-(trifluoromethyl)trifluoroethoxy]tetrafluoropropionic acid 12.671 da(a). 081
mol) with 15.54 ml of 0.2N sodium hydroxide to the neutral point (phenolphthalene indicator), a neutralization equivalent of 407.69 (calculated value 408) was obtained.

Add 1 mL of excess 0.2N NaOH and bring the solution to 50T.
Frozen in rLL Carius tubes. Then 10mL of water
Ammonium persulfate 0.25y1 water 102mL + Na2
A solution of 200.2y of O3.5FI and 3.1y of tetrafluoroethylene were added separately with freezing and the tube was sealed. The tube was rotated overnight at room temperature to obtain a clear solution and solid polymer. The solution was separated and acidified to obtain a gel that was almost soluble in ether.The ether was removed and the solution was dried under vacuum for 10 minutes.
100℃/10,000p by drying at 0℃
A copolymer 3.2y whose film was compressed by Si was obtained.
The copolymer showed strong absorption of -COOH (profound absorption at 3p and 5.7p) in the infrared rays. 3-[2-(trifluorethenoxy)-1-(trifluoromethyl)trifluoroethoxy] neutralized with a slight excess of 0.2N sodium hydroxide according to the general method of Use Example D(1). Tetrafluoropropionic acid 6y (0.015 mol)
, ammonium persulfate in 10 mL of water 0.25 y1 water 10
ml of Na2S2O3.5H200.029 and 10y of tetrafluoroethylene was rotated at room temperature overnight, then cooled and opened.

Claims (1)

[Claims] 1 Contacting SO_3 with a compound of the formula ROOC-CF_2-CF_2-OR^1 [wherein R and R^1 may be the same or different and are alkyl having 1 to 6 carbon atoms] A method for producing ROOC-CF_2-COF, comprising: 2. The method according to claim 1, wherein R is methyl or ethyl.